// bind 除了返回是函数以外，它 的参数和 call 一样


const person = {
    fullName: function(email=null,phone=null) {
        console.log(this.firstName + " " + this.lastName+" "+email+" "+phone)
    }
}
const person1 = {
    firstName:"Bill",
    lastName: "Gates",
}
const person2 = {
    firstName:"Steve",
    lastName: "Jobs",
}

person.fullName.bind(person1)()

person.fullName.bind(person2)() // Steve Jobs null null

person.fullName.bind(person1,'qq@123.com','123456')() // Bill Gates qq@123.com 123456

person.fullName.bind(person2,['qq@123.com'],['123456'])() // Steve Jobs qq@123.com 123456

person.fullName.bind(person2,['qq@123.com','123456'])() // Steve Jobs qq@123.com,123456 null